1. Field of the Invention
This invention relates to a massager which exerts a percussive massage effect with nodes having variable spacing.
2. Background Art
Power operated massagers are often used to treat muscle tension and fatigue. Massagers that exert a percussive effect on the body are preferred over massagers which generate a rubbing action, since the latter type of massager can cause irritation or other discomfort to the recipient.
Application Ser. No. 09/475,810, filed by same assignee on Dec. 30, 1999, published Oct. 4, 2001 as No. US2001/0027280A1 discloses a percussive massager and is incorporated by reference herein. The massager includes a motor having an output shaft extending from either side thereof, the motor being affixed within the housing by a motor support unit. A rocker arm is pivotally mounted to the motor support unit. A pair of connecting rods, each mounted to either end of the output shaft, are also mounted to the rocker arm. A pair of spaced-apart nodes are mounted to the rocker arm wherein the motor drives the rocker arm in an asynchronous manner thereby imparting a percussive massage effect to the massage nodes.
Prior to the percussive massager of application Ser. No. 09/475,810, prior art percussive massagers typically included a single eccentrically driven connecting rod for oscillating a centrally pivoted rocker arm carrying a pair of massage nodes to achieve a single connecting rod design required that the rocker arm have a substantial cross-section to accommodate the bending load resulting from a single input. Additionally, the single input design required the connecting rod to be alternatively loaded in compression and tension making it difficult to elastically attach the connecting rod to the rocker arm. The pair of connecting rods asynchronously driving the rocker arm overcame these limitations.
However, the prior art percussive massagers do not offer any flexibility or adjustment of the spacing of the massage nodes or formations without manual adjustment of the spacing. Accordingly, it is the goal of the present invention to provide a simple, low-cost and low-weight percussive massager providing variable spacing of the massage nodes or formations.